Fig. 5: Pattern-Recognition Receptors(PRRs)
on and in Defense Cells

To recognize PAMPs such as those
listed above, various body cells have a variety of corresponding receptors
called pattern-recognition receptors or PRRs capable of binding specifically
to conserved portions of these molecules.Cells
that typically have pattern recognition receptors include macrophages,
dendritic cells,
endothelial cells,
mucosal epithelial cells, and lymphocytes. Many
pattern-recognition receptors are located on the surface of
these cells where they can interact with PAMPs on the surface of microbes.
Others PRRs are found within
the phagolysosomes of phagocytes where they can interact with
PAMPs located within microbes that have been phagocytosed. Some PRRs
are found in the cytosol of the cell.